Sexual dimorphism is often assumed to result from balancing the strength of antagonistic selection in favor of dimorphism against the degree of constraint imposed by the shared genome of the sexes, reflected in the B matrix of genetic intersexual covariances. To investigate the totality of forces shaping dimorphism, we reparameterized the Lande equation to predict changes in trait averages and trait differences between the sexes. As genetic constraints on the evolution of dimorphism in response to antagonistic selection become larger, dimorphism will tend to respond more rapidly to concordant selection (which favors the same direction of change in male and female traits) than to antagonistic selection. When we apply this theory to four empirical estimates of B in Drosophila melanogaster, the indirect responses of dimorphism to concordant selection are of comparable or larger magnitude than the direct responses of dimorphism to antagonistic selection in two suites of traits with typical levels of intersex correlation. Antagonistic selection is more important in two suites of traits where the intersex correlations are unusually low. This suggests that the evolution of sexual dimorphism may sometimes be dominated by concordant selection rather than antagonistic selection.

中文翻译：

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预测性二态性对直接和间接选择的多元响应。

人们通常认为性二态性是通过平衡有利于二态性的对抗选择的强度与性别共享基因组所施加的限制程度之间的平衡而产生的，这反映在遗传的两性共变的B矩阵中。为了研究形成双态的力的总和，我们重新参数化了Lande方程，以预测性状平均值的变化和两性之间的性状差异。随着对拮抗选择的反应对二态性进化的遗传约束变得更大，与对立选择相比，双态性倾向于更一致地响应一致选择（这有利于男性和女性性状的相同变化方向）。当我们将此理论应用于B中的四个经验估计时果蝇（Drosophila melanogaster），在同性相关的两个典型水平上，双态对配偶选择的间接响应与双态对拮抗选择的直接响应具有可比性或更大。对性选择在两性特征之间的相关性异常低的两个方面更为重要。这表明性二态性的进化有时可能由一致选择而非对抗性选择主导。